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. 1993 Oct 1;295(Pt 1):31–40. doi: 10.1042/bj2950031

Modulation of insulin secretion from normal rat islets by inhibitors of the post-translational modifications of GTP-binding proteins.

S A Metz 1, M E Rabaglia 1, J B Stock 1, A Kowluru 1
PMCID: PMC1134816  PMID: 8216234

Abstract

Many GTP-binding proteins (GBPs) are modified by mevalonic acid (MVA)-dependent isoprenylation, carboxyl methylation or palmitoylation. The effects of inhibitors of these processes on insulin release were studied. Intact pancreatic islets were shown to synthesize and metabolize MVA and to prenylate several candidate proteins. Culture with lovastatin (to inhibit synthesis of endogenous MVA) caused the accumulation in the cytosol of low-M(r) GBPs (labelled by the [alpha-32P]GTP overlay technique), suggesting a disturbance of membrane association. Concomitantly, lovastatin pretreatment reduced glucose-induced insulin release by about 50%; co-provision of 100-200 microM MVA totally prevented this effect. Perillic acid, a purported inhibitor of the prenylation of small GBPs, also markedly reduced glucose-induced insulin secretion. Furthermore, both N-acetyl-S-trans,trans-farnesyl-L-cysteine (AFC), which inhibited the base-labile carboxyl methylation of GBPs in islets or in transformed beta-cells, and cerulenic acid, an inhibitor of protein palmitoylation, also reduced nutrient-induced secretion; an inactive analogue of AFC (which did not inhibit carboxyl methylation in islets) had no effect on secretion. In contrast with nutrients, the effects of agonists that induce secretion by directly activating distal components in signal transduction (such as a phorbol ester or mastoparan) were either unaffected or enhanced by lovastatin or AFC. These data are compatible with the hypothesis that post-translational modifications are required for one or more stimulatory GBPs to promote proximal step(s) in fuel-induced insulin secretion, whereas one or more inhibitory GBPs might reduce secretion at a more distal locus.

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  1. Ahnert-Hilger G., Wegenhorst U., Stecher B., Spicher K., Rosenthal W., Gratz M. Exocytosis from permeabilized bovine adrenal chromaffin cells is differently modulated by guanosine 5'-[gamma-thio]triphosphate and guanosine 5'-[beta gamma-imido]triphosphate. Evidence for the involvement of various guanine nucleotide-binding proteins. Biochem J. 1992 Jun 1;284(Pt 2):321–326. doi: 10.1042/bj2840321. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Alberts A. W., Chen J., Kuron G., Hunt V., Huff J., Hoffman C., Rothrock J., Lopez M., Joshua H., Harris E. Mevinolin: a highly potent competitive inhibitor of hydroxymethylglutaryl-coenzyme A reductase and a cholesterol-lowering agent. Proc Natl Acad Sci U S A. 1980 Jul;77(7):3957–3961. doi: 10.1073/pnas.77.7.3957. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Backlund P. S., Jr GTP-stimulated carboxyl methylation of a soluble form of the GTP-binding protein G25K in brain. J Biol Chem. 1992 Sep 15;267(26):18432–18439. [PubMed] [Google Scholar]
  4. Balch W. E. Small GTP-binding proteins in vesicular transport. Trends Biochem Sci. 1990 Dec;15(12):473–477. doi: 10.1016/0968-0004(90)90301-q. [DOI] [PubMed] [Google Scholar]
  5. Baxter A., Fitzgerald B. J., Hutson J. L., McCarthy A. D., Motteram J. M., Ross B. C., Sapra M., Snowden M. A., Watson N. S., Williams R. J. Squalestatin 1, a potent inhibitor of squalene synthase, which lowers serum cholesterol in vivo. J Biol Chem. 1992 Jun 15;267(17):11705–11708. [PubMed] [Google Scholar]
  6. Berrow N. S., Milligan G., Morgan N. G. Immunological characterization of the guanine-nucleotide binding proteins Gi and Go in rat islets of Langerhans. J Mol Endocrinol. 1992 Apr;8(2):103–108. doi: 10.1677/jme.0.0080103. [DOI] [PubMed] [Google Scholar]
  7. Berrow N. S., Morgan N. G. Evidence for the presence of low molecular mass GTP-binding proteins in rat islets of Langerhans. Biochem Soc Trans. 1990 Jun;18(3):485–486. doi: 10.1042/bst0180485. [DOI] [PubMed] [Google Scholar]
  8. Best L., Lebrun P., Saceda M., Garcia-Morales P., Hubinont C., Juvent M., Herchuelz A., Malaisse-Lagae F., Valverde I., Malaisse W. J. Impairment of insulin release by methylation inhibitors. Biochem Pharmacol. 1984 Jul 1;33(13):2033–2039. doi: 10.1016/0006-2952(84)90570-7. [DOI] [PubMed] [Google Scholar]
  9. Black S. D. Development of hydrophobicity parameters for prenylated proteins. Biochem Biophys Res Commun. 1992 Aug 14;186(3):1437–1442. doi: 10.1016/s0006-291x(05)81567-0. [DOI] [PubMed] [Google Scholar]
  10. Blank J. L., Brattain K. A., Exton J. H. Activation of cytosolic phosphoinositide phospholipase C by G-protein beta gamma subunits. J Biol Chem. 1992 Nov 15;267(32):23069–23075. [PubMed] [Google Scholar]
  11. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  12. Burgoyne R. D., Morgan A. Low molecular mass GTP-binding proteins of adrenal chromaffin cells are present on the secretory granule. FEBS Lett. 1989 Mar 13;245(1-2):122–126. doi: 10.1016/0014-5793(89)80204-2. [DOI] [PubMed] [Google Scholar]
  13. Burstein E. S., Linko-Stentz K., Lu Z. J., Macara I. G. Regulation of the GTPase activity of the ras-like protein p25rab3A. Evidence for a rab3A-specific GAP. J Biol Chem. 1991 Feb 15;266(5):2689–2692. [PubMed] [Google Scholar]
  14. Buss J. E., Mumby S. M., Casey P. J., Gilman A. G., Sefton B. M. Myristoylated alpha subunits of guanine nucleotide-binding regulatory proteins. Proc Natl Acad Sci U S A. 1987 Nov;84(21):7493–7497. doi: 10.1073/pnas.84.21.7493. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Butrynski J. E., Jones T. L., Backlund P. S., Jr, Spiegel A. M. Differential isoprenylation of carboxy-terminal mutants of an inhibitory G-protein alpha-subunit: neither farnesylation nor geranylgeranylation is sufficient for membrane attachment. Biochemistry. 1992 Sep 1;31(34):8030–8035. doi: 10.1021/bi00149a037. [DOI] [PubMed] [Google Scholar]
  16. Campillo J. E., Ashcroft S. J. Protein carboxymethylation in rat islets of Langerhans. FEBS Lett. 1982 Feb 8;138(1):71–75. doi: 10.1016/0014-5793(82)80397-9. [DOI] [PubMed] [Google Scholar]
  17. Clarke S. Protein isoprenylation and methylation at carboxyl-terminal cysteine residues. Annu Rev Biochem. 1992;61:355–386. doi: 10.1146/annurev.bi.61.070192.002035. [DOI] [PubMed] [Google Scholar]
  18. Cormont M., Le Marchand-Brustel Y., Van Obberghen E., Spiegel A. M., Sharp G. W. Identification of G protein alpha-subunits in RINm5F cells and their selective interaction with galanin receptor. Diabetes. 1991 Sep;40(9):1170–1176. doi: 10.2337/diab.40.9.1170. [DOI] [PubMed] [Google Scholar]
  19. Crowell P. L., Chang R. R., Ren Z. B., Elson C. E., Gould M. N. Selective inhibition of isoprenylation of 21-26-kDa proteins by the anticarcinogen d-limonene and its metabolites. J Biol Chem. 1991 Sep 15;266(26):17679–17685. [PubMed] [Google Scholar]
  20. Fung B. K., Yamane H. K., Ota I. M., Clarke S. The gamma subunit of brain G-proteins is methyl esterified at a C-terminal cysteine. FEBS Lett. 1990 Jan 29;260(2):313–317. doi: 10.1016/0014-5793(90)80132-3. [DOI] [PubMed] [Google Scholar]
  21. Gingras D., Béliveau R. Guanine nucleotides stimulate carboxyl methylation of kidney cytosolic proteins. Biochim Biophys Acta. 1992 Aug 12;1136(2):150–154. doi: 10.1016/0167-4889(92)90250-f. [DOI] [PubMed] [Google Scholar]
  22. Goldstein J. L., Brown M. S. Regulation of the mevalonate pathway. Nature. 1990 Feb 1;343(6257):425–430. doi: 10.1038/343425a0. [DOI] [PubMed] [Google Scholar]
  23. Gomperts B. D. GE: a GTP-binding protein mediating exocytosis. Annu Rev Physiol. 1990;52:591–606. doi: 10.1146/annurev.ph.52.030190.003111. [DOI] [PubMed] [Google Scholar]
  24. Grand R. J., Owen D. The biochemistry of ras p21. Biochem J. 1991 Nov 1;279(Pt 3):609–631. doi: 10.1042/bj2790609. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Göke B., Williams J. A., Wishart M. J., De Lisle R. C. Low molecular mass GTP-binding proteins in subcellular fractions of the pancreas: regulated phosphoryl G proteins. Am J Physiol. 1992 Feb;262(2 Pt 1):C493–C500. doi: 10.1152/ajpcell.1992.262.2.C493. [DOI] [PubMed] [Google Scholar]
  26. Göke R., Göke B. Analysis of low molecular mass GTP-binding proteins in insulinoma-derived RINm5F cells by two-dimensional gel electrophoresis. Horm Metab Res. 1991 Jun;23(6):304–305. doi: 10.1055/s-2007-1003683. [DOI] [PubMed] [Google Scholar]
  27. Haklai R., Kloog Y. Relationship among methylation, isoprenylation, and GTP binding in 21- to 23-kDa proteins of neuroblastoma. Cell Mol Neurobiol. 1991 Aug;11(4):415–433. doi: 10.1007/BF00711422. [DOI] [PubMed] [Google Scholar]
  28. Hancock J. F., Magee A. I., Childs J. E., Marshall C. J. All ras proteins are polyisoprenylated but only some are palmitoylated. Cell. 1989 Jun 30;57(7):1167–1177. doi: 10.1016/0092-8674(89)90054-8. [DOI] [PubMed] [Google Scholar]
  29. Hillaire-Buys D., Mousli M., Landry Y., Bockaert J., Fehrentsz J. A., Carrette J., Rouot B. Insulin releasing effects of mastoparan and amphiphilic substance P receptor antagonists on RINm5F insulinoma cells. Mol Cell Biochem. 1992 Feb 12;109(2):133–138. doi: 10.1007/BF00229767. [DOI] [PubMed] [Google Scholar]
  30. Huzoor-Akbar, Wang W., Kornhauser R., Volker C., Stock J. B. Protein prenylcysteine analog inhibits agonist-receptor-mediated signal transduction in human platelets. Proc Natl Acad Sci U S A. 1993 Feb 1;90(3):868–872. doi: 10.1073/pnas.90.3.868. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Huzoor-Akbar, Winegar D. A., Lapetina E. G. Carboxyl methylation of platelet rap1 proteins is stimulated by guanosine 5'-(3-O-thio)triphosphate. J Biol Chem. 1991 Mar 5;266(7):4387–4391. [PubMed] [Google Scholar]
  32. Iñiguez-Lluhi J. A., Simon M. I., Robishaw J. D., Gilman A. G. G protein beta gamma subunits synthesized in Sf9 cells. Functional characterization and the significance of prenylation of gamma. J Biol Chem. 1992 Nov 15;267(32):23409–23417. [PubMed] [Google Scholar]
  33. Klinz F. J., Seifert R., Schwaner I., Gausepohl H., Frank R., Schultz G. Generation of specific antibodies against the rap1A, rap1B and rap2 small GTP-binding proteins. Analysis of rap and ras proteins in membranes from mammalian cells. Eur J Biochem. 1992 Jul 1;207(1):207–213. doi: 10.1111/j.1432-1033.1992.tb17039.x. [DOI] [PubMed] [Google Scholar]
  34. Knight D. E., von Grafenstein H., Athayde C. M. Calcium-dependent and calcium-independent exocytosis. Trends Neurosci. 1989 Nov;12(11):451–458. doi: 10.1016/0166-2236(89)90095-7. [DOI] [PubMed] [Google Scholar]
  35. Koch G., Mohr C., Just I., Aktories K. Posttranslational isoprenylation of rho protein is a prerequisite for its interaction with mastoparan and other amphiphilic agents. Biochem Biophys Res Commun. 1992 Jul 15;186(1):448–454. doi: 10.1016/s0006-291x(05)80828-9. [DOI] [PubMed] [Google Scholar]
  36. Koch N., Hämmerling G. J. The HLA-D-associated invariant chain binds palmitic acid at the cysteine adjacent to the membrane segment. J Biol Chem. 1986 Mar 5;261(7):3434–3440. [PubMed] [Google Scholar]
  37. Koffer A., Gomperts B. D. Soluble proteins as modulators of the exocytotic reaction of permeabilised rat mast cells. J Cell Sci. 1989 Nov;94(Pt 3):585–591. doi: 10.1242/jcs.94.3.585. [DOI] [PubMed] [Google Scholar]
  38. Kowluru A., Rana R. S., MacDonald M. J. Phospholipid methyltransferase activity in pancreatic islets: activation by calcium. Arch Biochem Biophys. 1985 Oct;242(1):72–81. doi: 10.1016/0003-9861(85)90481-3. [DOI] [PubMed] [Google Scholar]
  39. Leonard S., Beck L., Sinensky M. Inhibition of isoprenoid biosynthesis and the post-translational modification of pro-p21. J Biol Chem. 1990 Mar 25;265(9):5157–5160. [PubMed] [Google Scholar]
  40. Li G., Regazzi R., Roche E., Wollheim C. B. Blockade of mevalonate production by lovastatin attenuates bombesin and vasopressin potentiation of nutrient-induced insulin secretion in HIT-T15 cells. Probable involvement of small GTP-binding proteins. Biochem J. 1993 Jan 15;289(Pt 2):379–385. doi: 10.1042/bj2890379. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Magee A. I., Gutierrez L., McKay I. A., Marshall C. J., Hall A. Dynamic fatty acylation of p21N-ras. EMBO J. 1987 Nov;6(11):3353–3357. doi: 10.1002/j.1460-2075.1987.tb02656.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Maltese W. A., Aprille J. R. Relation of mevalonate synthesis to mitochondrial ubiquinone content and respiratory function in cultured neuroblastoma cells. J Biol Chem. 1985 Sep 25;260(21):11524–11529. [PubMed] [Google Scholar]
  43. Maltese W. A. Posttranslational modification of proteins by isoprenoids in mammalian cells. FASEB J. 1990 Dec;4(15):3319–3328. doi: 10.1096/fasebj.4.15.2123808. [DOI] [PubMed] [Google Scholar]
  44. Maltese W. A., Sheridan K. M. Isoprenylated proteins in cultured cells: subcellular distribution and changes related to altered morphology and growth arrest induced by mevalonate deprivation. J Cell Physiol. 1987 Dec;133(3):471–481. doi: 10.1002/jcp.1041330307. [DOI] [PubMed] [Google Scholar]
  45. Maltese W. A., Sheridan K. M., Repko E. M., Erdman R. A. Post-translational modification of low molecular mass GTP-binding proteins by isoprenoid. J Biol Chem. 1990 Feb 5;265(4):2148–2155. [PubMed] [Google Scholar]
  46. Matteoli M., Takei K., Cameron R., Hurlbut P., Johnston P. A., Südhof T. C., Jahn R., De Camilli P. Association of Rab3A with synaptic vesicles at late stages of the secretory pathway. J Cell Biol. 1991 Nov;115(3):625–633. doi: 10.1083/jcb.115.3.625. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Metz S. A., Dunlop M. Stimulation of insulin release by phospholipase D. A potential role for endogenous phosphatidic acid in pancreatic islet function. Biochem J. 1990 Sep 1;270(2):427–435. doi: 10.1042/bj2700427. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Metz S. A. Epinephrine impairs insulin release by a mechanism distal to calcium mobilization. Similarity to lipoxygenase inhibitors. Diabetes. 1988 Jan;37(1):65–73. doi: 10.2337/diab.37.1.65. [DOI] [PubMed] [Google Scholar]
  49. Metz S. A. Lipoxygenase inhibitors reduce insulin secretion without impairing calcium mobilization. Endocrinology. 1987 Jun;120(6):2534–2546. doi: 10.1210/endo-120-6-2534. [DOI] [PubMed] [Google Scholar]
  50. Mitchell J., Northup J. K., Schimmer B. P. Defective guanyl nucleotide-binding protein beta gamma subunits in a forskolin-resistant mutant of the Y1 adrenocortical cell line. Proc Natl Acad Sci U S A. 1992 Oct 1;89(19):8933–8937. doi: 10.1073/pnas.89.19.8933. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Morgan A., Burgoyne R. D. Exo1 and Exo2 proteins stimulate calcium-dependent exocytosis in permeabilized adrenal chromaffin cells. Nature. 1992 Feb 27;355(6363):833–836. doi: 10.1038/355833a0. [DOI] [PubMed] [Google Scholar]
  52. Musha T., Kawata M., Takai Y. The geranylgeranyl moiety but not the methyl moiety of the smg-25A/rab3A protein is essential for the interactions with membrane and its inhibitory GDP/GTP exchange protein. J Biol Chem. 1992 May 15;267(14):9821–9825. [PubMed] [Google Scholar]
  53. Ohara-Imaizumi M., Kameyama K., Kawae N., Takeda K., Muramatsu S., Kumakura K. Regulatory role of the GTP-binding protein, G(o), in the mechanism of exocytosis in adrenal chromaffin cells. J Neurochem. 1992 Jun;58(6):2275–2284. doi: 10.1111/j.1471-4159.1992.tb10974.x. [DOI] [PubMed] [Google Scholar]
  54. Omura S. The antibiotic cerulenin, a novel tool for biochemistry as an inhibitor of fatty acid synthesis. Bacteriol Rev. 1976 Sep;40(3):681–697. doi: 10.1128/br.40.3.681-697.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. Ong O. C., Ota I. M., Clarke S., Fung B. K. The membrane binding domain of rod cGMP phosphodiesterase is posttranslationally modified by methyl esterification at a C-terminal cysteine. Proc Natl Acad Sci U S A. 1989 Dec;86(23):9238–9242. doi: 10.1073/pnas.86.23.9238. [DOI] [PMC free article] [PubMed] [Google Scholar]
  56. Padfield P. J., Balch W. E., Jamieson J. D. A synthetic peptide of the rab3a effector domain stimulates amylase release from permeabilized pancreatic acini. Proc Natl Acad Sci U S A. 1992 Mar 1;89(5):1656–1660. doi: 10.1073/pnas.89.5.1656. [DOI] [PMC free article] [PubMed] [Google Scholar]
  57. Peffley D., Sinensky M. Regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase synthesis by a non-sterol mevalonate-derived product in Mev-1 cells. Apparent translational control. J Biol Chem. 1985 Aug 25;260(18):9949–9952. [PubMed] [Google Scholar]
  58. Philips M. R., Abramson S. B., Kolasinski S. L., Haines K. A., Weissmann G., Rosenfeld M. G. Low molecular weight GTP-binding proteins in human neutrophil granule membranes. J Biol Chem. 1991 Jan 15;266(2):1289–1298. [PubMed] [Google Scholar]
  59. Philips M. R., Pillinger M. H., Staud R., Volker C., Rosenfeld M. G., Weissmann G., Stock J. B. Carboxyl methylation of Ras-related proteins during signal transduction in neutrophils. Science. 1993 Feb 12;259(5097):977–980. doi: 10.1126/science.8438158. [DOI] [PubMed] [Google Scholar]
  60. Pérez-Sala D., Tan E. W., Cañada F. J., Rando R. R. Methylation and demethylation reactions of guanine nucleotide-binding proteins of retinal rod outer segments. Proc Natl Acad Sci U S A. 1991 Apr 15;88(8):3043–3046. doi: 10.1073/pnas.88.8.3043. [DOI] [PMC free article] [PubMed] [Google Scholar]
  61. Rana R. S., Kowluru A., MacDonald M. J. Enzymes of phospholipid metabolism in rat pancreatic islets: subcellular distribution and the effect of glucose and calcium. J Cell Biochem. 1986;32(2):143–150. doi: 10.1002/jcb.240320206. [DOI] [PubMed] [Google Scholar]
  62. Regazzi R., Kikuchi A., Takai Y., Wollheim C. B. The small GTP-binding proteins in the cytosol of insulin-secreting cells are complexed to GDP dissociation inhibitor proteins. J Biol Chem. 1992 Sep 5;267(25):17512–17519. [PubMed] [Google Scholar]
  63. Regazzi R., Ullrich S., Kahn R. A., Wollheim C. B. Redistribution of ADP-ribosylation factor during stimulation of permeabilized cells with GTP analogues. Biochem J. 1991 May 1;275(Pt 3):639–644. doi: 10.1042/bj2750639. [DOI] [PMC free article] [PubMed] [Google Scholar]
  64. Repko E. M., Maltese W. A. Post-translational isoprenylation of cellular proteins is altered in response to mevalonate availability. J Biol Chem. 1989 Jun 15;264(17):9945–9952. [PubMed] [Google Scholar]
  65. Robertson R. P., Seaquist E. R., Walseth T. F. G proteins and modulation of insulin secretion. Diabetes. 1991 Jan;40(1):1–6. doi: 10.2337/diab.40.1.1. [DOI] [PubMed] [Google Scholar]
  66. Rotrosen D., Gallin J. I., Spiegel A. M., Malech H. L. Subcellular localization of Gi alpha in human neutrophils. J Biol Chem. 1988 Aug 5;263(22):10958–10964. [PubMed] [Google Scholar]
  67. Rowe P. M., Wright L. S., Siegel F. L. Calmodulin N-methyltransferase. Partial purification and characterization. J Biol Chem. 1986 May 25;261(15):7060–7069. [PubMed] [Google Scholar]
  68. Schafer W. R., Kim R., Sterne R., Thorner J., Kim S. H., Rine J. Genetic and pharmacological suppression of oncogenic mutations in ras genes of yeast and humans. Science. 1989 Jul 28;245(4916):379–385. doi: 10.1126/science.2569235. [DOI] [PubMed] [Google Scholar]
  69. Schlesinger M. J., Malfer C. Cerulenin blocks fatty acid acylation of glycoproteins and inhibits vesicular stomatitis and Sindbis virus particle formation. J Biol Chem. 1982 Sep 10;257(17):9887–9890. [PubMed] [Google Scholar]
  70. Simonds W. F., Butrynski J. E., Gautam N., Unson C. G., Spiegel A. M. G-protein beta gamma dimers. Membrane targeting requires subunit coexpression and intact gamma C-A-A-X domain. J Biol Chem. 1991 Mar 25;266(9):5363–5366. [PubMed] [Google Scholar]
  71. Sontag J. M., Thierse D., Rouot B., Aunis D., Bader M. F. A pertussis-toxin-sensitive protein controls exocytosis in chromaffin cells at a step distal to the generation of second messengers. Biochem J. 1991 Mar 1;274(Pt 2):339–347. doi: 10.1042/bj2740339. [DOI] [PMC free article] [PubMed] [Google Scholar]
  72. Spiegel A. M., Backlund P. S., Jr, Butrynski J. E., Jones T. L., Simonds W. F. The G protein connection: molecular basis of membrane association. Trends Biochem Sci. 1991 Sep;16(9):338–341. doi: 10.1016/0968-0004(91)90139-m. [DOI] [PubMed] [Google Scholar]
  73. Staufenbiel M. Fatty acids covalently bound to erythrocyte proteins undergo a differential turnover in vivo. J Biol Chem. 1988 Sep 25;263(27):13615–13622. [PubMed] [Google Scholar]
  74. Takai Y., Kaibuchi K., Kikuchi A., Kawata M. Small GTP-binding proteins. Int Rev Cytol. 1992;133:187–230. doi: 10.1016/s0074-7696(08)61861-6. [DOI] [PubMed] [Google Scholar]
  75. Tan E. W., Rando R. R. Identification of an isoprenylated cysteine methyl ester hydrolase activity in bovine rod outer segment membranes. Biochemistry. 1992 Jun 23;31(24):5572–5578. doi: 10.1021/bi00139a021. [DOI] [PubMed] [Google Scholar]
  76. Tooze S. A., Weiss U., Huttner W. B. Requirement for GTP hydrolysis in the formation of secretory vesicles. Nature. 1990 Sep 13;347(6289):207–208. doi: 10.1038/347207a0. [DOI] [PubMed] [Google Scholar]
  77. Ullrich S., Wollheim C. B. GTP-dependent inhibition of insulin secretion by epinephrine in permeabilized RINm5F cells. Lack of correlation between insulin secretion and cyclic AMP levels. J Biol Chem. 1988 Jun 25;263(18):8615–8620. [PubMed] [Google Scholar]
  78. Vallar L., Biden T. J., Wollheim C. B. Guanine nucleotides induce Ca2+-independent insulin secretion from permeabilized RINm5F cells. J Biol Chem. 1987 Apr 15;262(11):5049–5056. [PubMed] [Google Scholar]
  79. Volker C., Lane P., Kwee C., Johnson M., Stock J. A single activity carboxyl methylates both farnesyl and geranylgeranyl cysteine residues. FEBS Lett. 1991 Dec 16;295(1-3):189–194. doi: 10.1016/0014-5793(91)81415-5. [DOI] [PubMed] [Google Scholar]
  80. Volker C., Miller R. A., McCleary W. R., Rao A., Poenie M., Backer J. M., Stock J. B. Effects of farnesylcysteine analogs on protein carboxyl methylation and signal transduction. J Biol Chem. 1991 Nov 15;266(32):21515–21522. [PubMed] [Google Scholar]
  81. Walworth N. C., Goud B., Kabcenell A. K., Novick P. J. Mutational analysis of SEC4 suggests a cyclical mechanism for the regulation of vesicular traffic. EMBO J. 1989 Jun;8(6):1685–1693. doi: 10.1002/j.1460-2075.1989.tb03560.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  82. Watson E. L., DiJulio D., Kauffman D., Iversen J., Robinovitch M. R., Izutsu K. T. Evidence for G proteins in rat parotid plasma membranes and secretory granule membranes. Biochem J. 1992 Jul 15;285(Pt 2):441–449. doi: 10.1042/bj2850441. [DOI] [PMC free article] [PubMed] [Google Scholar]
  83. Wei C., Lutz R., Sinensky M., Macara I. G. p23rab2, a ras-like GTPase with a -GGGCC C-terminus, is isoprenylated but not detectably carboxymethylated in NIH3T3 cells. Oncogene. 1992 Mar;7(3):467–473. [PubMed] [Google Scholar]
  84. Yokokawa N., Komatsu M., Takeda T., Aizawa T., Yamada T. Mastoparan, a wasp venom, stimulates insulin release by pancreatic islets through pertussis toxin sensitive GTP-binding protein. Biochem Biophys Res Commun. 1989 Feb 15;158(3):712–716. doi: 10.1016/0006-291x(89)92779-4. [DOI] [PubMed] [Google Scholar]

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